A rock is dropped from the top of a tall tower. Half a second later another rock, twice as massive as the first, is dropped. Ignoring air resistance.
Correct answer: A. The distance between the rocks increases while both are falling.
- A. The distance between the rocks increases while both are falling.
- B. The acceleration is greater for the more massive rock.
- C. They strike the ground more than half a second apart.
- D. They strike the ground with the same kinetic energy.
Explanation
The correct answer is Option A: The distance between the rocks increases while both are falling. The first rock is released before the second and starts accelerating immediately due to gravity. When the second rock is released, it begins to fall with the same acceleration but starts from rest, whereas the first rock already has velocity. Consequently, the distance between them increases. Option B is incorrect because all objects accelerate at the same rate in free fall regardless of mass. Option C is incorrect because the time difference between the releases is maintained until impact. Option D is incorrect because the second rock, being more massive, will strike the ground with greater kinetic energy.
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